www.tinc-vpn.org Git - tinc/blob - src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2010 Guus Sliepen <guus@tinc-vpn.org>
   5                   2006      Scott Lamb <slamb@slamb.org>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License along
  18     with this program; if not, write to the Free Software Foundation, Inc.,
  19     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20 */
  21
  22 #include "system.h"
  23
  24 #include <openssl/pem.h>
  25 #include <openssl/rsa.h>
  26 #include <openssl/rand.h>
  27 #include <openssl/err.h>
  28 #include <openssl/evp.h>
  29
  30 #include "avl_tree.h"
  31 #include "conf.h"
  32 #include "connection.h"
  33 #include "device.h"
  34 #include "event.h"
  35 #include "graph.h"
  36 #include "logger.h"
  37 #include "net.h"
  38 #include "netutl.h"
  39 #include "process.h"
  40 #include "protocol.h"
  41 #include "route.h"
  42 #include "subnet.h"
  43 #include "utils.h"
  44 #include "xalloc.h"
  45
  46 char *myport;
  47
  48 bool read_rsa_public_key(connection_t *c) {
  49         FILE *fp;
  50         char *fname;
  51         char *key;
  52
  53         if(!c->rsa_key) {
  54                 c->rsa_key = RSA_new();
  55 //              RSA_blinding_on(c->rsa_key, NULL);
  56         }
  57
  58         /* First, check for simple PublicKey statement */
  59
  60         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  61                 BN_hex2bn(&c->rsa_key->n, key);
  62                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  63                 free(key);
  64                 return true;
  65         }
  66
  67         /* Else, check for PublicKeyFile statement and read it */
  68
  69         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
  70                 fp = fopen(fname, "r");
  71
  72                 if(!fp) {
  73                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  74                                    fname, strerror(errno));
  75                         free(fname);
  76                         return false;
  77                 }
  78
  79                 free(fname);
  80                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
  81                 fclose(fp);
  82
  83                 if(c->rsa_key)
  84                         return true;            /* Woohoo. */
  85
  86                 /* If it fails, try PEM_read_RSA_PUBKEY. */
  87                 fp = fopen(fname, "r");
  88
  89                 if(!fp) {
  90                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  91                                    fname, strerror(errno));
  92                         free(fname);
  93                         return false;
  94                 }
  95
  96                 free(fname);
  97                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
  98                 fclose(fp);
  99
 100                 if(c->rsa_key) {
 101 //                              RSA_blinding_on(c->rsa_key, NULL);
 102                         return true;
 103                 }
 104
 105                 logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s",
 106                            fname, strerror(errno));
 107                 return false;
 108         }
 109
 110         /* Else, check if a harnessed public key is in the config file */
 111
 112         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 113         fp = fopen(fname, "r");
 114
 115         if(fp) {
 116                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 117                 fclose(fp);
 118         }
 119
 120         free(fname);
 121
 122         if(c->rsa_key)
 123                 return true;
 124
 125         /* Try again with PEM_read_RSA_PUBKEY. */
 126
 127         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 128         fp = fopen(fname, "r");
 129
 130         if(fp) {
 131                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 132 //              RSA_blinding_on(c->rsa_key, NULL);
 133                 fclose(fp);
 134         }
 135
 136         free(fname);
 137
 138         if(c->rsa_key)
 139                 return true;
 140
 141         logger(LOG_ERR, "No public key for %s specified!", c->name);
 142
 143         return false;
 144 }
 145
 146 bool read_rsa_private_key(void) {
 147         FILE *fp;
 148         char *fname, *key, *pubkey;
 149         struct stat s;
 150
 151         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 152                 if(!get_config_string(lookup_config(config_tree, "PublicKey"), &pubkey)) {
 153                         logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
 154                         return false;
 155                 }
 156                 myself->connection->rsa_key = RSA_new();
 157 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 158                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 159                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
 160                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 161                 free(key);
 162                 free(pubkey);
 163                 return true;
 164         }
 165
 166         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 167                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 168
 169         fp = fopen(fname, "r");
 170
 171         if(!fp) {
 172                 logger(LOG_ERR, "Error reading RSA private key file `%s': %s",
 173                            fname, strerror(errno));
 174                 free(fname);
 175                 return false;
 176         }
 177
 178 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 179         if(fstat(fileno(fp), &s)) {
 180                 logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'",
 181                                 fname, strerror(errno));
 182                 free(fname);
 183                 return false;
 184         }
 185
 186         if(s.st_mode & ~0100700)
 187                 logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
 188 #endif
 189
 190         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 191         fclose(fp);
 192
 193         if(!myself->connection->rsa_key) {
 194                 logger(LOG_ERR, "Reading RSA private key file `%s' failed: %s",
 195                            fname, strerror(errno));
 196                 free(fname);
 197                 return false;
 198         }
 199
 200         free(fname);
 201         return true;
 202 }
 203
 204 /*
 205   Read Subnets from all host config files
 206 */
 207 void load_all_subnets(void) {
 208         DIR *dir;
 209         struct dirent *ent;
 210         char *dname;
 211         char *fname;
 212         avl_tree_t *config_tree;
 213         config_t *cfg;
 214         subnet_t *s, *s2;
 215         node_t *n;
 216         bool result;
 217
 218         xasprintf(&dname, "%s/hosts", confbase);
 219         dir = opendir(dname);
 220         if(!dir) {
 221                 logger(LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
 222                 free(dname);
 223                 return;
 224         }
 225
 226         while((ent = readdir(dir))) {
 227                 if(!check_id(ent->d_name))
 228                         continue;
 229
 230                 n = lookup_node(ent->d_name);
 231                 #ifdef _DIRENT_HAVE_D_TYPE
 232                 //if(ent->d_type != DT_REG)
 233                 //      continue;
 234                 #endif
 235
 236                 xasprintf(&fname, "%s/hosts/%s", confbase, ent->d_name);
 237                 init_configuration(&config_tree);
 238                 result = read_config_file(config_tree, fname);
 239                 free(fname);
 240                 if(!result)
 241                         continue;
 242
 243                 if(!n) {
 244                         n = new_node();
 245                         n->name = xstrdup(ent->d_name);
 246                         node_add(n);
 247                 }
 248
 249                 for(cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
 250                         if(!get_config_subnet(cfg, &s))
 251                                 continue;
 252
 253                         if((s2 = lookup_subnet(n, s))) {
 254                                 s2->expires = -1;
 255                         } else {
 256                                 subnet_add(n, s);
 257                         }
 258                 }
 259
 260                 exit_configuration(&config_tree);
 261         }
 262
 263         closedir(dir);
 264 }
 265
 266 /*
 267   Configure node_t myself and set up the local sockets (listen only)
 268 */
 269 bool setup_myself(void) {
 270         config_t *cfg;
 271         subnet_t *subnet;
 272         char *name, *hostname, *mode, *afname, *cipher, *digest;
 273         char *fname = NULL;
 274         char *address = NULL;
 275         char *envp[5];
 276         struct addrinfo *ai, *aip, hint = {0};
 277         bool choice;
 278         int i, err;
 279
 280         myself = new_node();
 281         myself->connection = new_connection();
 282
 283         myself->hostname = xstrdup("MYSELF");
 284         myself->connection->hostname = xstrdup("MYSELF");
 285
 286         myself->connection->options = 0;
 287         myself->connection->protocol_version = PROT_CURRENT;
 288
 289         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 290                 logger(LOG_ERR, "Name for tinc daemon required!");
 291                 return false;
 292         }
 293
 294         if(!check_id(name)) {
 295                 logger(LOG_ERR, "Invalid name for myself!");
 296                 free(name);
 297                 return false;
 298         }
 299
 300         myself->name = name;
 301         myself->connection->name = xstrdup(name);
 302         xasprintf(&fname, "%s/hosts/%s", confbase, name);
 303         read_config_file(config_tree, fname);
 304         free(fname);
 305
 306         if(!read_rsa_private_key())
 307                 return false;
 308
 309         if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
 310                 myport = xstrdup("655");
 311
 312         if(!atoi(myport)) {
 313                 struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
 314                 sockaddr_t sa;
 315                 if(!ai || !ai->ai_addr)
 316                         return false;
 317                 free(myport);
 318                 memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
 319                 sockaddr2str(&sa, NULL, &myport);
 320         }
 321
 322         /* Read in all the subnets specified in the host configuration file */
 323
 324         cfg = lookup_config(config_tree, "Subnet");
 325
 326         while(cfg) {
 327                 if(!get_config_subnet(cfg, &subnet))
 328                         return false;
 329
 330                 subnet_add(myself, subnet);
 331
 332                 cfg = lookup_config_next(config_tree, cfg);
 333         }
 334
 335         /* Check some options */
 336
 337         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 338                 myself->options |= OPTION_INDIRECT;
 339
 340         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 341                 myself->options |= OPTION_TCPONLY;
 342
 343         if(myself->options & OPTION_TCPONLY)
 344                 myself->options |= OPTION_INDIRECT;
 345
 346         get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
 347         get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
 348         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 349         strictsubnets |= tunnelserver;
 350
 351         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 352                 if(!strcasecmp(mode, "router"))
 353                         routing_mode = RMODE_ROUTER;
 354                 else if(!strcasecmp(mode, "switch"))
 355                         routing_mode = RMODE_SWITCH;
 356                 else if(!strcasecmp(mode, "hub"))
 357                         routing_mode = RMODE_HUB;
 358                 else {
 359                         logger(LOG_ERR, "Invalid routing mode!");
 360                         return false;
 361                 }
 362                 free(mode);
 363         }
 364
 365         if(get_config_string(lookup_config(config_tree, "Forwarding"), &mode)) {
 366                 if(!strcasecmp(mode, "off"))
 367                         forwarding_mode = FMODE_OFF;
 368                 else if(!strcasecmp(mode, "internal"))
 369                         forwarding_mode = FMODE_INTERNAL;
 370                 else if(!strcasecmp(mode, "kernel"))
 371                         forwarding_mode = FMODE_KERNEL;
 372                 else {
 373                         logger(LOG_ERR, "Invalid forwarding mode!");
 374                         return false;
 375                 }
 376                 free(mode);
 377         }
 378
 379         choice = true;
 380         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
 381         if(choice)
 382                 myself->options |= OPTION_PMTU_DISCOVERY;
 383
 384         choice = true;
 385         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
 386         if(choice)
 387                 myself->options |= OPTION_CLAMP_MSS;
 388
 389         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 390
 391 #if !defined(SOL_IP) || !defined(IP_TOS)
 392         if(priorityinheritance)
 393                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 394 #endif
 395
 396         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 397                 macexpire = 600;
 398
 399         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 400                 if(maxtimeout <= 0) {
 401                         logger(LOG_ERR, "Bogus maximum timeout!");
 402                         return false;
 403                 }
 404         } else
 405                 maxtimeout = 900;
 406
 407         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 408                 if(!strcasecmp(afname, "IPv4"))
 409                         addressfamily = AF_INET;
 410                 else if(!strcasecmp(afname, "IPv6"))
 411                         addressfamily = AF_INET6;
 412                 else if(!strcasecmp(afname, "any"))
 413                         addressfamily = AF_UNSPEC;
 414                 else {
 415                         logger(LOG_ERR, "Invalid address family!");
 416                         return false;
 417                 }
 418                 free(afname);
 419         }
 420
 421         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 422
 423         /* Generate packet encryption key */
 424
 425         if(get_config_string
 426            (lookup_config(config_tree, "Cipher"), &cipher)) {
 427                 if(!strcasecmp(cipher, "none")) {
 428                         myself->incipher = NULL;
 429                 } else {
 430                         myself->incipher = EVP_get_cipherbyname(cipher);
 431
 432                         if(!myself->incipher) {
 433                                 logger(LOG_ERR, "Unrecognized cipher type!");
 434                                 return false;
 435                         }
 436                 }
 437         } else
 438                 myself->incipher = EVP_bf_cbc();
 439
 440         if(myself->incipher)
 441                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 442         else
 443                 myself->inkeylength = 1;
 444
 445         myself->connection->outcipher = EVP_bf_ofb();
 446
 447         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 448                 keylifetime = 3600;
 449
 450         keyexpires = now + keylifetime;
 451
 452         /* Check if we want to use message authentication codes... */
 453
 454         if(get_config_string(lookup_config(config_tree, "Digest"), &digest)) {
 455                 if(!strcasecmp(digest, "none")) {
 456                         myself->indigest = NULL;
 457                 } else {
 458                         myself->indigest = EVP_get_digestbyname(digest);
 459
 460                         if(!myself->indigest) {
 461                                 logger(LOG_ERR, "Unrecognized digest type!");
 462                                 return false;
 463                         }
 464                 }
 465         } else
 466                 myself->indigest = EVP_sha1();
 467
 468         myself->connection->outdigest = EVP_sha1();
 469
 470         if(get_config_int(lookup_config(config_tree, "MACLength"), &myself->inmaclength)) {
 471                 if(myself->indigest) {
 472                         if(myself->inmaclength > myself->indigest->md_size) {
 473                                 logger(LOG_ERR, "MAC length exceeds size of digest!");
 474                                 return false;
 475                         } else if(myself->inmaclength < 0) {
 476                                 logger(LOG_ERR, "Bogus MAC length!");
 477                                 return false;
 478                         }
 479                 }
 480         } else
 481                 myself->inmaclength = 4;
 482
 483         myself->connection->outmaclength = 0;
 484
 485         /* Compression */
 486
 487         if(get_config_int(lookup_config(config_tree, "Compression"), &myself->incompression)) {
 488                 if(myself->incompression < 0 || myself->incompression > 11) {
 489                         logger(LOG_ERR, "Bogus compression level!");
 490                         return false;
 491                 }
 492         } else
 493                 myself->incompression = 0;
 494
 495         myself->connection->outcompression = 0;
 496
 497         /* Done */
 498
 499         myself->nexthop = myself;
 500         myself->via = myself;
 501         myself->status.reachable = true;
 502         node_add(myself);
 503
 504         graph();
 505
 506         if(strictsubnets)
 507                 load_all_subnets();
 508
 509         /* Open device */
 510
 511         if(!setup_device())
 512                 return false;
 513
 514         /* Run tinc-up script to further initialize the tap interface */
 515         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 516         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 517         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 518         xasprintf(&envp[3], "NAME=%s", myself->name);
 519         envp[4] = NULL;
 520
 521         execute_script("tinc-up", envp);
 522
 523         for(i = 0; i < 5; i++)
 524                 free(envp[i]);
 525
 526         /* Run subnet-up scripts for our own subnets */
 527
 528         subnet_update(myself, NULL, true);
 529
 530         /* Open sockets */
 531
 532         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 533
 534         hint.ai_family = addressfamily;
 535         hint.ai_socktype = SOCK_STREAM;
 536         hint.ai_protocol = IPPROTO_TCP;
 537         hint.ai_flags = AI_PASSIVE;
 538
 539         err = getaddrinfo(address, myport, &hint, &ai);
 540
 541         if(err || !ai) {
 542                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 543                            gai_strerror(err));
 544                 return false;
 545         }
 546
 547         listen_sockets = 0;
 548
 549         for(aip = ai; aip; aip = aip->ai_next) {
 550                 listen_socket[listen_sockets].tcp =
 551                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 552
 553                 if(listen_socket[listen_sockets].tcp < 0)
 554                         continue;
 555
 556                 listen_socket[listen_sockets].udp =
 557                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 558
 559                 if(listen_socket[listen_sockets].udp < 0)
 560                         continue;
 561
 562                 ifdebug(CONNECTIONS) {
 563                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 564                         logger(LOG_NOTICE, "Listening on %s", hostname);
 565                         free(hostname);
 566                 }
 567
 568                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 569                 listen_sockets++;
 570         }
 571
 572         freeaddrinfo(ai);
 573
 574         if(listen_sockets)
 575                 logger(LOG_NOTICE, "Ready");
 576         else {
 577                 logger(LOG_ERR, "Unable to create any listening socket!");
 578                 return false;
 579         }
 580
 581         return true;
 582 }
 583
 584 /*
 585   initialize network
 586 */
 587 bool setup_network(void) {
 588         now = time(NULL);
 589
 590         init_events();
 591         init_connections();
 592         init_subnets();
 593         init_nodes();
 594         init_edges();
 595         init_requests();
 596
 597         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 598                 if(pinginterval < 1) {
 599                         pinginterval = 86400;
 600                 }
 601         } else
 602                 pinginterval = 60;
 603
 604         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 605                 pingtimeout = 5;
 606         if(pingtimeout < 1 || pingtimeout > pinginterval)
 607                 pingtimeout = pinginterval;
 608
 609         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 610                 maxoutbufsize = 10 * MTU;
 611
 612         if(!setup_myself())
 613                 return false;
 614
 615         return true;
 616 }
 617
 618 /*
 619   close all open network connections
 620 */
 621 void close_network_connections(void) {
 622         avl_node_t *node, *next;
 623         connection_t *c;
 624         char *envp[5];
 625         int i;
 626
 627         for(node = connection_tree->head; node; node = next) {
 628                 next = node->next;
 629                 c = node->data;
 630                 c->outgoing = NULL;
 631                 terminate_connection(c, false);
 632         }
 633
 634         for(list_node_t *node = outgoing_list->head; node; node = node->next) {
 635                 outgoing_t *outgoing = node->data;
 636
 637                 if(outgoing->event)
 638                         event_del(outgoing->event);
 639         }
 640
 641         list_delete_list(outgoing_list);
 642
 643         if(myself && myself->connection) {
 644                 subnet_update(myself, NULL, false);
 645                 terminate_connection(myself->connection, false);
 646                 free_connection(myself->connection);
 647         }
 648
 649         for(i = 0; i < listen_sockets; i++) {
 650                 close(listen_socket[i].tcp);
 651                 close(listen_socket[i].udp);
 652         }
 653
 654         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 655         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 656         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 657         xasprintf(&envp[3], "NAME=%s", myself->name);
 658         envp[4] = NULL;
 659
 660         exit_requests();
 661         exit_edges();
 662         exit_subnets();
 663         exit_nodes();
 664         exit_connections();
 665         exit_events();
 666
 667         execute_script("tinc-down", envp);
 668
 669         if(myport) free(myport);
 670
 671         for(i = 0; i < 4; i++)
 672                 free(envp[i]);
 673
 674         close_device();
 675
 676         return;
 677 }